Heat-curable powder coating compositions, which after the coating has cured result in a matt surface and simple method for producing same

ABSTRACT

The invention relates to heat-curable powder coating compositions, which after the coating has cured result in a matt surface and to a simple method for producing same

The invention relates to thermosetting powder coating compositions whichhave a matt surface after the coating is cured, and also to a simplemethod for their production.

Heat-curable powder coating materials do not emit any organic solventson application, and therefore clearly possess environmental advantagesover liquid paints. Crosslinking under hot conditions takes place viapolyaddition reactions or polycondensation reactions between thefunctional groups present in the binders. Typical binder systems areepoxy resins with curing agents based on amines, amidines, acids,anhydrides; carboxyl polyesters or polyacrylates with curing agentsbased on epoxides; hydroxyl polyesters or polyacrylates withcrosslinkers based on blocked isocyanates; polyacrylates containingepoxide groups with dicarboxylic acids as crosslinkers, carboxylpolyesters or polyacrylates with crosslinkers based onβ-hydroxyalkylamides, etc. As well as the technical coatings properties,the various binder systems differ particularly in the stability tooutdoor weathering. The pure binder systems lead in general to highlyglossy surfaces, with a gloss of >80 scale divisions (DIN 67530/ISO2813, incident angle 60°), when they are processed in a one-shot processwith only one co-reactant, e.g., crosslinker and resin, and are inducedto cure.

There is considerable interest in coating systems which endow asubstrate with a uniformly even and matt surface. The reason for this isprimarily practical. Glossy surfaces require a far higher degree ofcleaning than do matt surfaces. Furthermore, it may be desirable onsafety grounds to avoid highly reflecting surfaces. In wide areas ofapplication in the powder coatings industry, such as architectural,automotive, and metal-furnishing segments, etc., there is a rise indemand in matt (10-30 units) and semimatt (30-50 units) surfaces,measured as reflectometer values to DIN 67530/ISO 2813 at an incidentangle of 60°.

The most simple principle for obtaining a matt surface is to admix thepowder coating material with smaller or greater amounts—depending on theextent of the desired matt effect—of fillers, such as chalk, finelydivided silicon dioxide or barium sulfate, for example. These additions,though, produce a deterioration in the technical coatings filmproperties, such as adhesion, flexibility, impact strength, andchemicals resistance.

Although the addition of substances incompatible with the coatingmaterial, such as waxes or cellulose derivatives, for example, doesproduce a distinct matting, slight changes during extrusion lead tofluctuations in the surface gloss and to a “fade-out” effect in darkshades. The reproducibility of the matt effect is not guaranteed. EP0698645 describes the production of matt powder coatings by dry-blendingof at least two separately produced hydroxylalkylamide powder coatingmaterials. U.S. Pat. No. 3,842,035 therefore proposes producing mattpowder coatings by dry-blending ready-made powder coating materialshaving sufficiently different reactivities, i.e., powder coatingmaterials having very short and very long gelling times. The bindersused are acrylic resins, alkyd resins, and—preferably—epoxy resins.WO-A-89/06674 describes the production of satin-gloss or matt surfacesby dry blending, in other words physical blends of ready-made powdercoating materials, which are composed of different binder systems.

DE 2 324 696 proposes a method for producing matt coatings by using aspecialty curing agent reacting with epoxide groups—the salt of cyclicamidines with certain polycarboxylic acids. According to this method,the powder coating material undergoes crosslinking with differentreactivity at different temperatures, thus forming, on the surface,microstructures which exhibit a matt surface. The application of thismethod, however, is confined to epoxide and carboxyl polyester/epoxidepowder coating materials, meaning that this method cannot be used toproduce coatings with sufficient weathering stability.

EP 366 608 likewise proposes a method for producing powder coatingshaving matt surfaces. It relates to powder coating materials based onepoxy resins or epoxide compounds, such as triglycidyl isocyanurate(TGIC), for example, with carboxyl-terminated polyester resins andmixtures of di-, tri- or tetrakis(β-carboxyethyl)cyclohexanones or-cyclopentanones. The matt effect here is attributed to the differencein reactivity between the aliphatic carboxylate groups of thecrosslinker and the aromatic carboxylate groups of thecarboxyl-terminated polyester resin.

Another patent specification, DE 3 232 463, describes powder coatingswith matt surfaces by joint extrusion of hydroxyl-terminated polyesterresins, epoxide compounds, such as TGIC, for example, and special,reversibly blocked polyisocyanates having free carboxylate groups.

U.S. Pat. No. 4,801,680 (EP 322 834) describes a heat-curable powdercoating material which consists of a particulate mixture comprising apolyester containing carboxylate groups and a β-hydroxyalkylamide.Following application to a substrate, this powder coating material leadsto glossy film surfaces. According to example 2 of U.S. Pat. No.4,801,680, the resulting film surfaces exhibit no film-surfacedeterioration after an accelerated weathering test has been carried outand using UV irradiation EP 520429 describes a resin compositioncomprising polyesters having different hydroxyl numbers. The resincomposition described necessarily comprises a substantially ungelledpolyester A, a substantially ungelled polyester B,tetramethoxymethylglycoluril as curing agent, and an organic sulfonicacid as catalyst.

Numerous further publications have appeared concerning the possibilitiesfor matting hydroxyalkylamide powder coatings, examples being R.Franiau, “Advances in β-Hydroxyalkylamide crosslinking chemistry” ECJ,(2002) 10, p 409ff; D. Fink, U. Kubilius, “Optimising the Matting ofPowder Coatings”, Powder Coatings Europe 2002, and R. Guida, “A NovelApproach to Produce Reduced Gloss β-Hydroxyl Alkylamide Powder Coatings”Powder Coating 2002 PCI Conference; D. Beccaria et al. “Modeling GlossControl in Polyester/β-Hydroxyalkylamide Powder Coatings Based on SPMStructure-Property Relationship”, Waterborne, High-Solids and PowderCoatings Symposium, Feb. 26-28, 2003, New Orleans, La., USA.

Laid-open specification KR 10-2009-0111720 (application number10-2008-0037454), with translated title “CYCLOALKANE DICARBOXAMIDECOMPOUNDS, THEIR PREPARATION AND APPLICATION” (see also J. Korean Ind.Eng. Chem., vol. 20, No. 2, April 2009, 195-200), discloses inparticular in example 1 the therein-named compoundN¹,N¹,N⁴,N⁴-tetrakis(2-hydroxyethyl)cyclohexane-1,4-dicarboxamide(formula 3). This compound according to FIG. 2 has only one peakaccording to DSC analysis, with a maximum peak at approximately 190° C.A cis/trans content for the compound is not stated. Furthermore,polyesters containing carboxyl groups, which are not precisely definedbut instead are indicated only by broad ranges of certain parameters(polyesters not unambiguously characterized and unknown on the marketwith this viscosity), are crosslinked with this compound and comparedwith the known β-hydroxyalkylamide, in this case named in example 3 as[N¹,N¹,N⁶,N⁶-tetrakis(2-hydroxyethyl)adipamide] (available as VESTAGONHAA 320 or PRIMID XL 552), in other words with curing agents from theprior art, and with long-established market products, which are known tolead to glossy surfaces on the coatings produced. In FIGS. 3 and 4, themetal panels are shown. There is no description to the effect that thecoatings in question are matt. Nor is this possible, since the coatingsobtained with the conventional curing agents are glossy.

Therefore, for matt and semimatt (<50 gloss units) powder coatingcompositions with hydroxylalkylamides, state of the art is what arecalled dry blends; in other words, the separate preparation of twohydroxyalkylamide powder coating materials is required, based onβ-hydroxyalkylamides, plus resins (polymers) with different acidnumbers, which are then supplied in the form of a dry blend to thegrinding operation. This involves considerable extra cost and effortand, in the event of deviation in a binder component, results in glossdeviations which take considerable extra cost and effort to correct.Furthermore, these dry blends undergo separation, including at thepremises of the end customer, with a resultant shift in gloss if thepowder coating, as is usual, is to be recycled.

It was an object of the invention to find thermosetting powder coatingcomposition which after the coating is cured exhibit a matt surface, andalso a simple method for their production.

This object is achieved by the new β-hydroxyalkylamides of the inventionas crosslinkers (curing agents), and also by the method of theinvention.

The invention provides a powder coating composition substantiallycomprising

-   A) at least one polymer containing carboxylate groups and having an    acid number of 5 to 350 mg KOH/g and a glass transition temperature    T_(g) of greater than 40° C.,-   and-   B) at least one β-hydroxyalkylamide having two or three or four    β-hydroxyalkylamide groups per molecule of the formula I

-    where-    R¹ and R² are, independently of one another, identical or different    radicals selected from alkyl radical, cycloalkyl radical, aryl    radical, aralkyl radical or alkenyl radical having 1-24 carbon    atoms, it being possible for the radicals also to contain    heteroatoms and/or functional groups,-    and where R¹ may also be hydrogen,-    and where R² may also be

-    and-    A is

-    where radicals R³ are, independently of one another, identical or    different radicals selected from hydrogen, alkyl radical, cycloalkyl    radical, aryl radical, aralkyl radical or alkenyl radical having    1-24 carbon atoms, it being possible for the radicals also to    contain heteroatoms and/or functional groups, and where two or more    substituents R³ may be linked with one another to form rings;-    where the β-hydroxyalkylamides are present in solid form below 150°    C.;-   C) optionally auxiliaries and/or additives;-    where the ratio of β-hydroxyalkylamide groups to the carboxylate    groups is between 0.5:1 to 1.5:1.

Surprisingly it has been found that through the use of the newβ-hydroxyalkylamides of formula I of the invention as crosslinkers it ispossible to obtain coatings having matt (10-30 units) and semimatt(30-50 units) surfaces, measured as reflectometer values to DIN67530/ISO 2813 at an incident angle of 60°.

Surprisingly it has been found that through the method of the invention,in a one-shot operation, in other words by joint extrusion of all of thecomponents, it is possible to obtain the powder coating composition ofthe invention, based on polymers containing carboxylate groups andβ-hydroxyalkylamides of the invention as crosslinkers.

In the context of this invention the terms crosslinker and curing agentare used synonymously.

There is no requirement for costly and involved dry blending of at leasttwo powder coating materials which differ in reactivity, on the basis ofβ-hydroxyalkylamides as crosslinkers. Furthermore, there is also no needfor a polyester mixture or polyacrylate mixture of at least two resinshaving different reactivities.

Co-reactants contemplated for the β-hydroxyalkylamide compounds used inaccordance with the invention for preparing the powder coatingcomposition are polymers A) containing carboxylate groups. Polymerswhich can be used are addition polymers, polycondensates, andpolyaddition compounds. In principle it is possible to use any polymerwhich contains at least two carboxylate groups and has a glasstransition temperature T_(g) greater than 40° C. Polymers containingcarboxylate groups that are suitable for the powder coating materials ofthe invention are those which have acid numbers of 5-350 mg KOH/g,preferably 15-150 mg KOH/g, with OH numbers <15 mg KOH/g. These polymerspreferably have at least two terminal carboxylate groups.

Particularly preferred in the context of the invention are polyacrylatesand/or polyesters containing carboxylate groups.

The polyesters A) containing carboxylate groups are preferably polyesterpolycarboxylic acids prepared from polyols and polycarboxylic acidsand/or derivatives thereof. The glass transition temperature T_(g) ofthese acidic polyesters is situated in a range from 40 to 80° C.,preferably 40 to 70° C.; their acid number varies from 5-250 mg KOH/g,preferably from 10 to 150 mg KOH/g, more preferably 12 to 120 mg KOH/g.The OH numbers are below 15 mg KOH/g. They have an average molecularweight M_(W) of 1000 to 10 000 g/mol, preferably 1500 to 9000 g/mol,more preferably of 2000 to 8000 g/mol.

The polyesters containing carboxylate groups for use in accordance withthe invention are prepared using polycarboxylic acids, such as oxalic,succinic, adipic, 2,2,4(2,4,4)-trimethyladipic, azelaic, sebacic,decanedicarboxylic, dodecanedicarboxylic, fumaric, phthalic,isophthalic, terephthalic, trimellitic, pyromellitic acid, for example.For the acidic polyesters, polyols used are, by way of example, thefollowing: ethylene glycol, 1,2- and 1,3-propanediol, 1,2-, 1,3-, 1,4-and 2,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, neopentylglycol, 1,12-dodecanediol, 2,2,4(2,4,4)-trimethyl-1,6-hexanediol,trimethylolpropane, glycerol, pentaerythritol,1,4-bishydroxymethylcyclohexane, cyclohexane-1,4-diol, diethyleneglycol, triethylene glycol, and dipropylene glycol. It is of course alsopossible for hydroxyl-containing polyesters, prepared by known methodsfrom polycarboxylic acids and polyols, to be reacted with polycarboxylicacids and/or polycarboxylic anhydrides to give the polyesterpolycarboxylic acids.

The polyester resins containing carboxylate groups are prepared by knownmethods, by esterification or transesterification of dihydric and/orpolyhydric linear or branched, aliphatic or cycloaliphatic polyols withpolybasic, preferably dibasic or polybasic aliphatic, cycloaliphatic oraromatic carboxylic acids or their anhydrides or esters thereof, in thepresence of an esterification or transesterification catalyst attemperatures up to about 250° C. and under reduced pressure toward theend.

Preferred polyols are 2,2-dimethyl-1,3-propanediol (neopentyl glycol),ethylene glycol, 1,4-butanediol, 1,6-hexanediol,1,4-dimethylolcyclohexane, 2,2-[bis(4-hydroxycyclohexyl)]propane,diethylene glycol, dipropylene glycol, glycerol, pentaerythritol etc.The polyol component preferably includes a high fraction of neopentylglycol in order to obtain very high glass transition temperatures.Preferred polybasic carboxylic acids are terephthalic acid, isophthalicacid, trimellitic acid, adipic acid, and/or 1,4-cyclohanedicarboxylicacid. The functionality of the preferred polyester resins containingcarboxylate groups is adjusted via the ratio of dibasic tomore-than-dibasic carboxylic acids.

Suitable acrylate polymers containing carboxylate groups possess an acidnumber of 10-350 mg KOH/g, preferably 20 to 300 mg KOH/g, and a glasstransition temperature T_(g) of greater than 40° C., preferably of 45 to100° C., prepared by homopolymerization or copolymerization of a monomermixture.

The polyacrylate comprises carboxylic acid groups and may be ahomopolymer or a copolymer.

Monomers which can be used are acrylic acid and/or methacrylic acid,C₁-C₄₀ alkyl esters and/or cycloalkyl esters of methacrylic acid and/oracrylic acid, hydroxyalkyl acrylates and/or hydroxyalkyl methacrylates,glycidyl methacrylate, glycidyl acrylate, 1,2-epoxybutyl acrylate,1,2-epoxybutyl methacrylate, 2,3-epoxycyclopentyl acrylate,2,3-epoxycyclopentyl methacrylate, and also the analogous amides, wherestyrene and/or derivatives thereof may also be present.

Preference is given to using butyl acrylate and/or butyl methacrylate,2-hydroxyethyl acrylate and/or 2-hydroxyethyl methacrylate, methylmethacrylate, styrene (meth)acrylic acid, and, optionally, furtherunsaturated monomers, with at least one monomer containing carboxylategroups being used.

Further suitable monomers are (cyclo)alkyl esters of acrylic ormethacrylic acid having 2 to 18 carbon atoms in the (cyclo)alkylradical. Examples of suitable and preferentially suitable monomers areethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate,n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl(meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl methacrylate,neopentyl methacrylate, isobornyl methacrylate,3,3,5-trimethylcyclohexyl methacrylate, and stearyl methacrylate.

Examples of monomers contemplated include styrene, vinyltoluene, andethylstyrene. Examples of are acrylic acid and methacrylic acid, whichare also used preferably, and also crotonic acid, itaconic acid, fumaricacid, maleic acid, and citaconic acid.

The polyacrylate preferably possesses an OH number of less than 10 mgKOH/g, an acid number of 5 to 350 mg KOH/g, preferably 20 to 300 mgKOH/g, more preferably of 30 to 250 mg KOH/g, a Tg of 40 to 110° C.,preferably 45 to 100° C., an M_(w) of 500 to 50 000 g/mol, preferably1000 to 30 000 g/mol, more preferably of 1500 to 20 000 g/mol.

As co-crosslinkers it is also possible to use epoxy resins. Thosecontemplated include, for example, glycidyl ethers and glycidyl esters,aliphatic epoxides, diglycidyl ethers based on bisphenol A, and glycidylmethacrylates. Examples of epoxides of these kinds are triglycidylisocyanurate (TGIC trade name: e.g., ARALDIT PT 810, Huntsman; TEPIC G,Nissan; Taida TGIC, Anhui Taida), mixtures of diglycidyl terephthalateand triglycidyl trimellitate (trade names, e.g., ARALDIT PT 910 and PT912, Huntsman), glycidyl esters of Versatic acid (trade name, e.g.,CARDURA E10, Shell), 3,4-epoxycyclohexylmethyl3′,4′-epoxycyclohexanecarboxylate (ECC), diglycidyl ethers based onbisphenol A (trade name, e.g., EPIKOTE 828, Shell), ethylhexyl glycidylether, butyl glycidyl ether, pentaerythritol tetraglycidyl ether, (tradename, e.g., POLYPDX R16, UPPC AG), and also other Polypox types havingfree epoxy groups. Mixtures can also be used. Preference is given tousing TEPIC G or ARALDIT PT 910 and 912. Co-crosslinkers of these kindscan be used at up to 50% by weight of the curing agent mixture that isused, composed of β-hydroxyalkylamide of the invention (matt curingagent) and co-crosslinker.

Surprisingly it has been found that β-hydroxyalkylamides having acyclohexane ring in the framework, the β-hydroxyalkylamides beingpresent in solid form below 150° C., as crosslinkers forcarboxyl-containing polymers in powder coating materials, lead to mattsurfaces after curing.

The β-hydroxyalkylamides B) may be prepared from various startingmaterials. A known reaction is that of β-hydroxyalkylamines with estersof carboxylic acids, the latter generating the parent structure (A).Depending on the selection of the starting materials, theβ-hydroxyalkylamides of the invention can be generated in this way.

Alternative but less preferred methods are based on other carboxylicacid derivatives, such as carboxylic acids, carbonyl chlorides,carboxylic anhydrides or other activated carboxylic acid derivatives,for example, as starting materials, which are reacted withβ-hydroxyalkylamines.

Suitable β-hydroxyalkylamines are those which have alkyl groups havingat least 2 to 10 carbon atoms in the hydrocarbon framework. The alkylgroups may be linear, branched or else cyclic. The alkyl groups maylikewise be substituted by heteroatoms, preferably oxygen, nitrogen.Furthermore, these alkyl groups may also contain functional groups,preferably carbonyl groups, carboxyl groups, amino groups, amide groups,urethane groups, and may carry an additional alkyl radical on thenitrogen.

Preferably in this invention the β-hydroxyalkylamides are prepared fromN-alkyl-1,2-alkanolamines and/or from N,N-bis-2-hydroxyalkylamines andesters of cyclohexanedicarboxylic acids.

Particular preference is given to using β-hydroxyalkylamines of theformulae II and/or III:

whereR¹ is hydrogen, methyl, ethyl, propyl,R² is methyl;

where radicals R¹ simultaneously or independently of one another arehydrogen, methyl, ethyl, propyl.

Particular preference in accordance with the invention is given to usingthe following compounds as starting materials for preparingβ-hydroxyalkylamides: diethanolamine (DEA), di-isopropropanolamine(DIPA), di-sec-butanolamine, N-methylethanolamine,N-methylisopropanolamine.

Suitable starting compounds for the substituent A in theβ-hydroxyalkylamides of the invention are 1,2-, 1,3-, and1-4-cyclohexanedicarboxylic acid derivatives, more particularly dialkylesters of cyclohexanedicarboxylic acids. These starting compounds mayhave any desired cis/trans content.

Preference is given to using compounds of the formula IV

where radicals R⁴ simultaneously or independently of one another aremethyl, ethyl, propyl, butyl.

Particular preference is given to using 1,4-substitutedcyclohexanedicarboxylic esters, very preferably dimethyl1,4-cyclohexyldicarboxylate.

The β-hydroxyalkylamides that are particularly preferred in accordancewith the invention, formed from dialkyl 1,4-cyclohexyldicarboxylates,preferably from dimethyl 1,4-cyclohexyldicarboxylate, have a transcontent, based on the position of the carboxyl groups on the cyclohexylring, of greater than or equal to 70 mol %, preferably greater than 80mol %, more preferably of greater than 85 mol %. For preparing thepreferred β-hydroxyalkylamides it is possible in this case to usedialkyl 1,4-cyclohexyldicarboxylates having any desired trans content.

The β-hydroxyalkylamides (I) of the invention are present in solid formbelow 150° C., preferably below 170° C., more preferably below 180° C.

Particularly preferred β-hydroxyalkylamides of the invention have thefollowing formulae:

whereR² is methyl,or

where R^(1A) is hydrogen and R^(1B) is methyl, ethyl, propyl,orR^(1A) is methyl, ethyl, propyl and R¹⁸ is hydrogen;andA is a 1,4-disubstituted cyclohexane ring of the formula

where the trans content of A is ≧70 mol %;and where the β-hydroxyalkylamides are present in solid form below 150°C.

The β-hydroxyalkylamide that is particularly preferred in accordancewith the invention, formed from dimethyl 1,4-cyclohexyldicarboxylate anddiethanolamine with four β-hydroxyalkylamide groups per molecule of theformula XII,

has a trans content on the cyclohexyl ring of greater than or equal to70 mol %, preferably greater than 80 mol %, and more preferably ofgreater than 85 mol %.

In order to achieve good technical coatings properties for the powdercoating composition, the ratio of β-hydroxyalkylamide groups to thecarboxylate groups of the polymers containing carboxylate groups ispreferably between 0.5 to 1.5:1, more preferably between 0.8 to 1.2:1.

The powder coating composition may be admixed with the auxiliaries andadditives C) that are customary in powder coating technology, such asflow control agents, e.g., polysilicones or acrylates, lightstabilizers, e.g., sterically hindered amines and/or absorbers,degassing agents (e.g., benzophenone), modified phenolic resins,catalysts and/or other auxiliary agents, as described in EP 669 353, forexample, in a total amount of 0.1% to 10% by weight. Fillers andpigments such as titanium dioxide, for example, can be added in anamount of up to 50% by weight of the overall composition.

In quantitative terms the constitution of the powder coatingcompositions is as follows:

% by weight Inventive β-hydroxyalkylamide 0.5 to 20  (matt curing agentB) preferably  1 to 15 Optional HAA curing agent  0 to 10 preferably 0to 8 Polymers A) containing 35 to 96 carboxylate groups preferably 50 to80 Optionally co-crosslinker(s) 0 to 5 preferably 0 to 3 Additives,fillers, pigments etc. C) 0.1 to 50  preferably  5 to 40

The powder coating compositions of the invention exhibit good storagestability in the storage test customary for powder coating materials, inaccordance with DIN EN ISO 8130-8, at temperatures of 30±1 and 40±1° C.,and are storable for >30 days.

In the particularly preferred embodiment of the invention, the powdercoating compositions of the invention comprise:

-   -   at least one polyester containing carboxylate groups and having        an acid number of 15 to 150 mg/KOH/g and a glass conversion        temperature of at least 40° C.,    -   at least one β-hydroxyalkylamide of the invention having at        least two or more, preferably four, β-hydroxyalkylamide groups,        or else mixtures thereof having the same and/or different        functionality,    -   and also, optionally, further additives and auxiliaries        customary for powder coating materials, such as, for example,        wetting, flow control or degassing agents, heat stabilizers or        UV stabilizers, pigments, dyes, fillers, co-crosslinkers.

The invention provides a method for producing a powder coatingcomposition substantially comprising

-   A) at least one polymer containing carboxylate groups and having an    acid number of 5 to 250 mg KOH/g and a glass transition temperature    T_(g) of greater than 40° C.,-    and-   B) at least one β-hydroxyalkylamide having two or three or four    β-hydroxyalkylamide groups per molecule of the formula I

-    where-    R¹ and R² are, independently of one another, identical or different    radicals selected from alkyl radical, cycloalkyl radical, aryl    radical, aralkyl radical or alkenyl radical having 1-24 carbon    atoms, it being possible for the radicals also to contain    heteroatoms and/or functional groups, and where R¹ may also be    hydrogen,-    and where R² may also be

-    and-    A is

-    where radicals R³ are, independently of one another, identical or    different radicals selected from hydrogen, alkyl radical, cycloalkyl    radical, aryl radical, aralkyl radical or alkenyl radical having    1-24 carbon atoms, it being possible for the radicals also to    contain heteroatoms and/or functional groups, and where two or more    substituents R³ may be linked with one another to form rings; where    the β-hydroxyalkylamides are present in solid form below 150° C.;-   C) optionally auxiliaries and/or additives;    where the ratio of β-hydroxyalkylamide groups to the carboxylate    groups is between 0.5:1 to 1.5:1;    in the melt by joint extrusion of all the components at temperatures    between 80 to 150° C.

The invention also provides a method for producing a powder coatingcomposition, comprisingN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according toformula XIIA as component B)

which has the following parameters:

-   -   1. a trans content on the cyclohexyl ring of greater than or        equal to 70 mol %, based on the total amount of all of the        isomers of        N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that        are present,    -   and    -   2. two endothermic peaks according to DSC analysis (differential        scanning calorimetry), where peak 1 is situated in the region of        140-170° C. with a maximum of 155-165° C., and peak 2 is        situated in the region of 170-210° C. with a maximum of 175-207°        C.,    -   and    -   3. the ratio of the enthalpies of the endothermic peak 1 to the        endothermic peak 2 is 1:1 to 1:5,    -   and    -   4. the XRPD spectrum of the powder sample in the x-ray        diffractometer, measured with Cu Kα radiation (1.541 Å), has the        following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

The invention also provides a method for producing a powder coatingcomposition, comprisingN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA as component B)

which has the following parameters:

-   -   1. a trans content on the cyclohexyl ring of greater than or        equal to 70 mol %, based on the total amount of all of the        isomers of        N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that        are present,    -   and    -   2. two endothermic peaks according to DSC analysis (differential        scanning calorimetry), where peak 1 is situated in the region of        140-170° C. with a maximum of 155-165° C., and peak 2 is        situated in the region of 170-210° C. with a maximum of 175-207°        C.,    -   and    -   3. the ratio of the enthalpies of the endothermic peak 1 to the        endothermic peak 2 is 1:1 to 1:5,    -   and    -   4. the XRPD spectrum of the powder sample in the x-ray        diffractometer, measured with Cu Kα radiation (1.541 Å), has the        following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

-   -   5. and which, according to x-ray structural analysis of a single        crystal, has the following parameters:

Crystal system: Orthorhombic Space group: Pbca Unit cell dimensions: a =10.06350(10) Å α = 90°. b = 11.85290(10) Å β = 90°. c = 14.6275(2) Å γ =90°. Volume: 1744.79(3) Å³

The powder coating composition of the invention is produced preferablyin the melt by joint extrusion of all the components A) to C) attemperatures between 80 to 150° C. The extrudate is subsequently cooled,ground, and sieved off or classified to a particle size of <120 μm,preferably <100 μm. The heat-curable and toxicologically flawless powdercoating composition produced in accordance with the invention thereforeconsists of a matrix obtained by joint extrusion of all the components.

In order to obtain the effect in accordance with the invention, namelythe formation of matt surfaces having a gloss to DIN 67530/ISO 2813 of<50 at an incident angle of 60°, it is possible to use numerous polymerscontaining carboxylate groups, more particularlycarboxylate-group-terminated polyesters or polyacrylates, which differin their functionality and reactivity. The desired gloss can thereforebe selected via the selected binder partner (polyester) in conjunctionwith the hydroxyalkylamide of the invention within a considerablespectrum (examples 1-7), with the formulation being otherwise the same.Example (8) with the polyacrylate deviates from this, since morecrosslinker is needed for the increased acid number, and a lower levelof pigmentation was selected in view of the anticipated greaterbrittleness.

The use of and the application of the powder coating materials forproducing coatings take place in accordance with methods customary forpowder coating materials, preferably by means of an electrostatic powdercoating sprayer device in accordance with the triboelectric or coronamethod or in accordance with the fluid-bed method.

At standard ambient temperatures, the powder coating compositionsproduced in accordance with the invention possess good storage stabilityand, after crosslinking between 150 to 220° C., exhibit good technicalcoatings properties, surfaces which flow out well in optical terms, andthe low gloss levels described.

In contrast to the prior art, the coatings obtained with the powdercoating compositions of the invention have visually very attractivesurfaces with good leveling (PCI evaluation table 8-10), which, however,are matt (10-30 units) and/or semimatt (30-50 units), measured asreflectometer values to DIN 67530/ISO 2813 at an incident angle of 60°,with no need for a dry blend or a polyester mixture or polyacrylatemixture (one-shot blend).

Beyond this variation, the possibility additionally exists of shiftingthe measured reflectometer value, to DIN 67530/ISO 2813 at an incidentangle of 60°, to higher levels, up to the re-acquisition of the highgloss of >80 scale divisions at the 60° angle. This is accomplished bypartially replacing the matt curing agent B) of the invention with astandard commercial β-hydroxyalkylamide having two or more than twoβ-hydroxyalkylamide groups, or mixtures thereof having differentfunctionalities.

The invention provides the use of a powder coating compositionsubstantially comprising

-   -   A) at least one polymer containing carboxylate groups and having        an acid number of 5 to 350 mg KOH/g and a glass transition        temperature T_(g) of greater than 40° C.,    -   and    -   B) at least one β-hydroxyalkylamide having two or three or four        β-hydroxyalkylamide groups per molecule of the formula I

-   -   where    -   R¹ and R² are, independently of one another, identical or        different radicals selected from alkyl radical, cycloalkyl        radical, aryl radical, aralkyl radical or alkenyl radical having        1-24 carbon atoms, it being possible for the radicals also to        contain heteroatoms and/or functional groups, and where R¹ may        also be hydrogen,    -   and where R² may also be

-   -   and    -   A is

-   -    where radicals R³ are, independently of one another, identical        or different radicals selected from hydrogen, alkyl radical,        cycloalkyl radical, aryl radical, aralkyl radical or alkenyl        radical having 1-24 carbon atoms, it being possible for the        radicals also to contain heteroatoms and/or functional groups,        and where two or more substituents R³ may be linked with one        another to form rings; where the β-hydroxyalkylamides are        present in solid form below 150° C.;    -   C) optionally auxiliaries and/or additives;    -   where the ratio of β-hydroxyalkylamide groups to the carboxylate        groups is between 0.5:1 to 1.5:1;    -   for producing coatings having matt surfaces, having a gloss to        DIN 67530/ISO 2813 of <50 at an incident angle of 60.

Provided especially preferably by the invention is a powder coatingcomposition which has the compoundN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA as component B),

which has the following parameters:

-   -   1. a trans content on the cyclohexyl ring of greater than or        equal to 70 mol %, based on the total amount of all of the        isomers of        N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that        are present, and    -   2. two endothermic peaks according to DSC analysis (differential        scanning calorimetry), where peak 1 is situated in the region of        140-170° C. with a to maximum of 155-165° C., and peak 2 is        situated in the region of 170-210° C. with a maximum of 175-207°        C.,    -   and    -   3. the ratio of the enthalpies of the endothermic peak 1 to the        endothermic peak 2 is 1:1 to 1:5, and    -   4. the XRPD spectrum of the powder sample in the x-ray        diffractometer, measured with Cu Kα radiation (1.541 Å), has the        following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

Description of the Particularly Preferred Component B):

Provided more preferably by the invention is a powder coatingcomposition comprising the β-hydroxyalkylamideN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA as component B), having a trans content on thecyclohexyl ring of greater than or equal to 70 mol %, preferably greaterthan 80 mol %, and more preferably of greater than 85 mol %, based onthe total amount of all of the isomers ofN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that arepresent.

Additionally this β-hydroxyalkylamide of the invention used as componentB), N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide accordingto the formula XIIA, has two endothermic peaks according to DSC analysis(differential scanning calorimetry): first a peak with a maximum(peak 1) of about 160° C., and a further, second peak with a maximum(peak 2) of about 190° C.; see the figures relating to the examples.Preferably, the first peak is situated in the range of 140-170° C. witha maximum of 155-165° C. and the second peak is situated in the range of170-210° C. with a maximum of 175-207° C.

More preferably, the first peak is situated in the range of 155-170° C.with a maximum of 158-165° C., and the second peak is situated in therange of 170-210° C. with a maximum of 180-205° C.

The ratio of the enthalpies of the endothermic peak 1 (˜160° C.) to theendothermic peak 2 (˜190° C.) may be 1:1 to 1:5, preferably 1:1 to 1:3.

The DSC measurements were carried out in accordance with DIN EN ISO11357-1 of March 2010. A heat flow difference calorimeter from themanufacturer Mettler-Toledo, model DSC 821, was used. The samples arerun once from −30° C. to 250° C. at 10 K/min.

The XRPD measurements on powder samples were carried out in an x-raydiffractometer using Cu Kα radiation (1.541 Å). In accordance with FIG.9, the following significant and characteristic 6 peaks of theβ-hydroxyalkylamideN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA were found:

Degrees 2theta ± Peak # 0.2 degree 2 theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

Especially preferred as component B) is the β-hydroxyalkylamideN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA having a trans content on the cyclohexyl ring ofgreater than or equal 92 mol %, preferably greater than 94 mol %, andmore preferably of greater than 96 mol %, and very preferably of greaterthan 98 mol %, based on the total amount of all of the isomers ofN,N,N′,W-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that arepresent.

The β-hydroxyalkylamide of the formula XIIA of the invention that isused as component B) is present in solid form below 175° C., preferablybelow 180° C., and more preferably of below 185° C.

The β-hydroxyalkylamide of the formula XIIA of the invention that isused as component B), having the features 1. to 4, was investigated bymeans of x-ray structural analysis of a single crystal. Comprehensivedetails relating to the measurement are summarized in annex 1. The x-raystructural analysis of a single crystal gave the following result forthe structure:

Crystal system: Orthorhombic Space group: Pbca Unit cell dimensions: a =10.06350(10) Å α = 90°. b = 11.85290(10) Å β = 90°. c = 14.6275(2) Å γ =90°. Volume: 1744.79(3) Å³

The values within the brackets indicate the measurement accuracy, ineach case in plus and minus, for the corresponding last digit or lasttwo digits, respectively.

Provided with very particular preference by the invention is a powdercoating composition which comprises the compoundN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA as component B)

which has the following parameters:

-   -   1. a trans content on the cyclohexyl ring of greater than or        equal to 70 mol %, based on the total amount of all of the        isomers of        N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that        are present,    -   and    -   2. two endothermic peaks according to DSC analysis (differential        scanning calorimetry), where peak 1 is situated in the region of        140-170° C. with a maximum of 155-165° C., and peak 2 is        situated in the region of 170-210° C. with a maximum of 175-207°        C.,    -   and    -   3. the ratio of the enthalpies of the endothermic peak 1 to the        endothermic peak 2 is 1:1 to 1:5, and    -   4. the XRPD spectrum of the powder sample in the x-ray        diffractometer, measured with Cu Kα radiation (1.541 Å), has the        following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

-   -   5. and which, according to x-ray structural analysis of a single        crystal, has the following parameters:

Crystal system: Orthorhombic Space group: Pbca Unit cell dimensions: a =10.06350(10) Å α = 90°. b = 11.85290(10) Å β = 90°. c = 14.6275(2) Å γ =90°. Volume: 1744.79(3) Å³

Preparation

The particularly preferredN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA which is used as component B) is obtainable by variousmethods:

First of all, as described precisely earlier on above, theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA is prepared, preferably solventlessly, in an extruder,intensive compounder, intensive mixer or static mixer, preferably in anextruder. For this preparation, temperatures of 100 to 180° C. areemployed. This is followed by recrystallization from a suitable solvent,preferably water. After dissolution at temperatures of 20-100° C. andcrystallization, theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA is obtained with the above-stated parameters. It canthen, subsequently, be washed with alcohols, preferably methanol, anddried. Drying takes place preferably at temperatures of 20-90° C., andcan also take place under reduced pressure.

Another variant of the preparation takes place as described preciselyearlier on above, by theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA being prepared in an extruder, intensive compounder,intensive mixer or static mixer, preferably in an extruder, preferablysolventlessly. In this case temperatures of 100 to 180° C. are employed.This is followed by a thermal conditioning at temperatures of 50-100°C., preferably at temperatures of 70-85° C. The time is more than 6hours, preferably more than 12 hours. Thermal conditioning may also takeplace under reduced pressure.

The particularly preferredN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA that is used as component B) may also take placediscontinuously in a solvent, in other words in a batch method.

The reaction is carried out in customary reactors. Operation may beunpressurized, using a reflux condenser, or under pressure, with aclosed reactor.

The synthesis is carried out in a solvent, preferably in alcohols,preferably methanol. The amount of solvent added is greater than 10% byweight, preferably greater than 15% by weight, based on the total amountof all the reactants (starting materials) used. This operation may takeplace under reflux, or else at relatively low temperatures, and alsorelatively high temperatures, under pressure. The preparation takesplace at temperatures of 20 to 120° C., preferably at 60 to 90° C., morepreferably at 70 to 85° C.

After crystallization has taken place, theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA is obtained, with the parameters stated above.

Furthermore, theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA can be prepared in closed apparatus under pressure attemperatures of 60 to 140° C. without addition of solvents.

The N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide accordingto the formula XIIA prepared in this way in a batch method can berecrystallized from suitable solvents, preferably from water oralcohols, preferably from methanol.

Furthermore, the preparation of theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA may also take place discontinuously without solvents.

The reaction is carried out in customary reactors. It is possible hereto operate using a reflux condenser. The preparation takes placepreferably at temperatures of 20 to 140° C., preferably 60 to 90° C.,more preferably at 70 to 85° C. The β-hydroxyalkylamide obtained in thisway in a batch method is then recrystallized from suitable solvents,preferably from water or alcohols, preferably from methanol. Aftercrystallization has taken place, theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA is obtained, with the parameters stated above.

The concentration of all of the isomers ofN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide in the endproduct after its preparation is 75% by mass, preferably 80% by mass,and more preferably 85% by mass.

This β-hydroxyalkylamide characterized and described here,N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide of the formulaXIIA, produces far-reaching matting in powder coatings, with a gloss ofless than 50 scale divisions at the 60° angle, as has been shown in theexamples. This product of the formula XIIA therefore differs clearlyfrom the β-hydroxyalkylamide disclosed in accordance with laid-openspecification KR 10-2009-0111720 (and from the β-hydroxyalkylamide fromKorean Ind. Eng. Chem., vol. 20, No. 2, April 2009, 195-200), asdemonstrated there in FIG. 2 on page 15, which has only one peakaccording to DSC analysis at about 190° C., and, as shown by comparativeexample 4c, does not lead to coatings having matt surfaces.

The invention also provides the use of a powder coating composition asdescribed above, comprisingN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according toformula XIIA as a component

which has the following parameters:

-   -   1. a trans content on the cyclohexyl ring of greater than or        equal to 70 mol %, based on the total amount of all of the        isomers of        N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that        are present,    -   and    -   2. two endothermic peaks according to DSC analysis (differential        scanning calorimetry), where peak 1 is situated in the region of        140-170° C. with a maximum of 155-165° C., and peak 2 is        situated in the region of 170-210° C. with a maximum of 175-207°        C.,    -   and    -   3. the ratio of the enthalpies of the endothermic peak 1 to the        endothermic peak 2 is 1:1 to 1:5,    -   and    -   4. the XRPD spectrum of the powder sample in the x-ray        diffractometer, measured with Cu Kα radiation (1.541 Å), has the        following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43for producing coatings having matt surfaces with <50 gloss units,measured as reflectometer values to DIN 67530/ISO 2813 with an incidentangle of 60°.

The invention also provides the use of a powder coating composition asdescribed above, comprisingN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according tothe formula XIIA as component B)

which has the following parameters:

-   1. a trans content on the cyclohexyl ring of greater than or equal    to 70 mol %, based on the total amount of all of the isomers of    N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that are    present, and-   2. two endothermic peaks according to DSC analysis (differential    scanning calorimetry), where peak 1 is situated in the region of    140-170° C. with a maximum of 155-165° C., and peak 2 is situated in    the region of 170-210° C. with a maximum of 175-207° C.,-    and-   3. the ratio of the enthalpies of the endothermic peak 1 to the    endothermic peak 2 is 1:1 to 1:5,-    and-   4. the XRPD spectrum of the powder sample in the x-ray    diffractometer, measured with Cu Kα radiation (1.541 Å), has the    following peaks:

Degrees 2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.705.31 3 17.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00 3.43

-   5. and which, according to x-ray structural analysis of a single    crystal, has the following parameters:

Crystal system: Orthorhombic Space group: Pbca Unit cell dimensions: a =10.06350(10) Å α = 90°. b = 11.85290(10) Å β = 90°. c = 14.6275(2) Å γ =90°. Volume: 1744.79(3) Å³for producing coatings having matt surfaces with <50 gloss units,measured as reactometer values to DIN 67530/ISO 2813 at an incidentangle of 60°.

EXAMPLES

The following examples and tables 1, 2, and 3 characterize thecomposition of the coating system and the properties of the respectivecoating after its application and curing.

Materials Used: 1) β-Hydroxyalkylamide

-   -   a) β-Hydroxyalkylamide (matt cutting agent) based on        1,4-cyclohexanedicarboxylic acid and diethanolamine, having four        β-hydroxyalkylamide groups per molecule, of the formula XII has        a trans content on the cyclohexyl ring of >90% (Evonik Degussa        GmbH, D).

trans-N,N,N′,N′-tetrakis(2-hydroxyethyl) % by mass 95.30cyclohexyl-1,4-diamide¹ cis-N,N,N′,N′-tetrakis(2-hydroxyethyl) % by mass0.28 cyclohexyl-1,4-diamide¹ Σ N,N,N′,N′-tetrakis(2-hydroxyethyl) % bymass 95.58 cyclohexyl-1,4-diamide¹ DEA¹ % by mass 0.18 OH number mgKOH/g 616 Base number mg KOH/g 3 Melting range ° C. 194-201 ¹Analyticalvalues by GC OH number: DIN 53240 Base number: DIN 53176 Melting range:DIN EN ISO 3146

-   -   b) VESTAGON® HA 320, OH number: 660-740 mg KOH/g, melting range:        115-130° C., (Evonik Degussa GmbH, D)

2) Polymers Containing Carboxylate Groups—Resins

-   -   a) Amorpher polyester:        -   Crylcoat® 2617-3, AN number: 33 mg KOH/g, Tg: 61° C., (Cytec            Inc., USA)        -   Crylcoat® 2618-3, AN number: 35 mg KOH/g, Tg: 61° C., (Cytec            Inc., USA)        -   Crylcoat® E 36988, AN number: 30 mg KOH/g, Tg: 54° C.,            (Cytec Inc., USA)        -   Uralac® P 800, AN number: 28 mg KOH/g, Tg: 61° C., DSM            Resins B.V., NL)        -   Uralac® P 865, AN number: 35 mg KOH/g, Tg: 56° C., (DSM            Resins B.V., NL)        -   Pulverol® 8120, AN number: 33 mg KOH/g, Tg: 60° C.,            (Neochimiki LV s.a., GR)        -   Pulverol® 8123, AN number: 33 mg KOH/g, Tg: 60° C.,            (Neochimiki LV s.a., GR)    -   b) Polyarclate        -   Joncryl® 819, AN number: 75 mg KOH/g, Tg: 57° C., (BASF AG.,            D)

3) Co-Crosslinker

-   -   a) Triglycidyl isocyanurate:        -   TEPIC®G, Epoxy equiv: <110 g/eq, Melting range: 90-125° C.,            (Nissan Chemical Ind. Ltd., J)

4) Other Formulating Ingredients:

-   -   Titanium dioxide, Kronos® 2160, (Kronos Titan GmbH, D),    -   Resiflow® PV 88, (Worlée-Chemie GmbH, D),    -   Benzoin, (Merck-Schuchard, D).

Powder Coating Material and Coating

The powder coating material was produced first by mixing all of thecomponents as per tables 1 and 2 at room temperature in a MIT mixer at500 rpm for 120 seconds and then, second, by joint extrusion in the meltat a temperature (barrel) of 90° C. (about 130° C. melt temperature).The stoichiometric ratio of acid groups of the polyester or polyacrylateto OH groups of the β-hydroxyalkylamides (curing agents) was about 1:1.When co-crosslinkers were used, they were taken into accountstoichiometrically in respect of the amount of curing agent.

The extrudate was subsequently cooled, ground, and sieved to a particlesize of <100 μm. The powder coating material produced in this way wasapplied using an electrostatic powder spraying unit at 60 KV todegreased steel panels (deep-drawn steel from Krüppel 210×70×0.8 mm)and/or aluminum panels (Q-panel AL-36 5005 H 14/08 0.8 mm) and baked ina forced-air drying oven at between 160 to 220° C. The cured coatingfilms had a film thickness of about 55-65 μm. The example data relate toa baking time of 20 minutes at 200° C.

TABLE 1 Testing according to characteristics of different polyesters andpolyacrylate Formulating examples with inventive β-hydroxyalkylamide 1a(matt cutting agent) and different resins Example 1 2 3 4 5 6 7 8β-Hydroxyalkylamide % by wt. 3.00 3.00 3.00 3.00 3.00 3.00 3.00 7.80 1aCRYLCOAT ® 2618-3 % by wt. 60.70 — — — — — — — CRYLCOAT ® E 36988 % bywt. — 60.70 — — — — — — PULVEROL ® 8120 % by wt. — — 60.70 — — — — —URALAC ® P 800 % by wt. — — — 60.70 — — — — URALAC ® P 865 % by wt. — —— — 60.70 — — — CRYLCOAT ® 2617-3 % by wt. — — — — — 60.70 — —PULVEROL ® 8123 % by wt. — — — — — — 60.70 — JONCRYL ® SCX 819 % by wt.— — — — — — — 66.00 KRONOS ® 2160 % by wt. 35.00 35.00 35.00 35.00 35.0035.00 35.00 25.00 RESIFLOW ® PV 88 % by wt. 1.00 1.00 1.00 1.00 1.001.00 1.00 1.00 Benzoin % by wt. 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.20Curing at 200° C. min 20 20 20 20 20 20 20 30 Film thickness μm 67-7157-66 57-59 57-61 66-73 54-60 52-59 58-62 Erichsen cupping mm >8 4 >85 >8 >8 >8 6 Ball impact direct in lb >80 >80 >80 >80 >80 >80 >80 20Ball impact reverse in lb 60 60 80 50 80 60 80 <10 Gloss 60° 

units 36 53 44 51 30 33 45 33 Gloss 85° 

units 44-48 62-67 53-59 60-64 39-43 41-43 55-61 59-65

By replacing the inventive β-hydroxyalkylamide 1a) by a standardcommercial β-hydroxyalkylamide, such as VESTAGON HA 320 1b), or else bymixtures with other commercial products with the same and/or differentfunctionality, it is possible to retain the gloss, at low levels ofadmixture, or, if desired, to shift it to higher values, with increasedadditivation or replacement. This is shown here in examples 9 to 13 byreference to a polyester.

Formulating examples with inventive β-hydroxyalkylamide 1a (matt curingagent) and different resins, and with commercial β-hydroxyalkylamide 1b)

TABLE 2 Example 9 10 11 12 13 β-Hydroxyalkylamide % by wt. 1.90 1.751.50 1.00 0.25 1a VESTAGON HA 320 % by wt. 1.10 1.25 1.50 2.00 2.75 1bCRYLCOAT ® 2617-3 % by wt. 60.70 60.70 60.70 60.70 60.70 KRONOS ® 2160 %by wt. 35.00 35.00 35.00 35.00 35.00 RESIFLOW ® PV 88 % by wt. 1.00 1.001.00 1.00 1.00 Benzoin % by wt. 0.30 0.30 0.30 0.30 0.30 Curing at 200°C. min 20 20 20 20 20 Film thickness μm 57-66 57-59 57-61 66-73 54-60Erichsen cupping mm >8 >8 >8 >8 >8 Ball impact direct inlb >80.00 >80.00 >80.00 >80.00 >80.00 Ball impact reverse in lb80 >80 >80 >80 >80 Gloss 60° 

units 53 57 62 83 94

As co-crosslinkers it is also possible to use epoxy resins. Examplescontemplated include glycidyl ethers and glycidyl esters, aliphaticepoxides, diglycidyl ethers based on bisphenol A, and glycidylmethacrylates. Examples of such epoxides are triglycidyl isocyanurate(TGIC trade names, e.g., ARALDIT PT 810, Huntsman; TEPIC G, Nissan;Taida TGIC, Anhui Taida), mixtures of diglycidyl terephthalate andtriglycidyl trimellitate (trade names, e.g., ARALDIT PT 910 and PT 912,Huntsman), glycidyl esters of Versatic acid (trade name, e.g., CARDURAE10, Shell), 3,4-epoxycyclohexylmethyl 3′,4′-epoxycyclohexanecarboxylate(ECC), diglycidyl ethers based on bisphenol A (trade name, e.g., EPIKOTE828, Shell), ethylhexyl glycidyl ether, butyl glycidyl ether,pentaerythritol tetraglycidyl ether, (trade name, e.g., POLYPDX R 16,UPPC AG), and also other Polypox types having free epoxy groups.Mixtures can also be used. Preference is given to using TEPIC G orARALDIT PT 910 and 912.

Co-crosslinkers of these kinds can be used at up to 50% by weight of thecuring agent mixture used, composed of matt curing agent andco-crosslinker.

Formulating examples with inventive β-hydroxyalkylamide 1a (matt curingagent) and co-crosslinker

TABLE 3 Example 14 15 16 17 β-Hydroxyalkylamide % by wt. 2.95 2.90 2.802.50 1a TEPIC ® G 3a % by wt. 0.05 0.10 0.20 0.50 CRYLCOAT ® 2617-3 % bywt. 60.70 60.70 60.70 60.70 KRONOS ® 2160 % by wt. 35.00 35.00 35.0035.00 RESIFLOW ® PV 88 % by wt. 1.00 1.00 1.00 1.00 Benzoin % by wt.0.30 0.30 0.30 0.30 Curing at 200° C. min 20 20 20 20 Film thickness μm50-56 50-55 53-62 45-51 Erichsen cupping mm >8 >8 >8 >8 Ball impactdirect in lb 60 >80 >80 >80 Ball impact reverse in lb <10 >80 >80 >80Gloss 60° 

units 32 44 45 53 Gloss 85° 

units 40-45 58-62 57-59 65-67

Examples 3a, b; 4a, b, c, d; 5

The DSC Measurements

The DSC measurements were carried out in accordance with DIN EN ISO11357-1 of March 2010.

A heat flow difference calorimeter from the manufacturer Mettler-Toledo,model: DSC 821 with serial number 5116131417 was used. The samples arerun once from −30° C. to 250° C. at 10 K/min.

Comprehensive Description of the Measurement Method:

-   -   1. Type (heat flow difference calorimeter or power-compensated        calorimeter), model and manufacturer of the DSC instrument used;    -   2. Material, nature, and type, and also, when necessary, mass of        the crucibles used;    -   3. Nature, purity, and volume flow rate of the flushing gas        used;    -   4. Nature of the calibration method and details of the        calibrating substances used, including source, mass, and other        properties significant for calibration;    -   5. Details concerning sampling, sample preparation, and        conditioning        1: Heat flow difference calorimeter    -   Manufacturer: Mettler-Toledo    -   Model: DSC 821    -   Serial number: 5116131417

2: Crucible Material: Ultrapure Aluminum

-   -   Size: 40 μl, without pin,    -   Mettler order No.: ME-26763    -   Mass including lid: about 48 mg

3: Flushing Gas: Nitrogen

-   -   Purity: 5.0 (>99.999% by volume)    -   Volume flow rate: 40 ml/min

4: Calibrating Method: Single

-   -   Material 1: indium    -   Mettler calibrating set ME-51119991    -   Mass: about 6 mg per weighing    -   Calibration of temperature (onset) and heat flow    -   Material 2: deionized water    -   Taken from in-house system    -   Mass: about 1 mg per weighing    -   Calibration of temperature (onset)        5: Sampling: from Supplied Sample Vials    -   Sample weighing mass: 8 to 10 mg    -   Sample preparation: pressed on the crucible base using die    -   Crucible lid: perforated    -   Measurement program: −30 to 250° C. 10 K/min 1×

Description of the XRPD Measurement:

The powder sample is pressed into a powder holder and is measured in aPhilips PW1800 x-ray diffractometer using Cu Kα radiation (1.541 Å)under the following conditions:

Excitation: 40 kV, 45 mA

Measuring range: 3°≦2θ≦40°Step size: 0.1° (2Theta)Time per step: 20 sRotation: ¼ revolution/secReceiving slit: coarseDivergence slit: automatic

Examples 3a, b; 4a, b, c, d

Product description, Substances used manufacturer Diethanolamine (DEA)Dow Chemical Dimethyl 1,4-cyclohexyldicarboxylate Dimethylester of 1,4-(DMCD) (distilled) trans content cyclohexanedicarboxylic acid, 15-35 mol% EASTMAN Sodium methoxide 30% strength in methanol

Example 3a

A three-neck flask with reflux condenser and glass stirrer is chargedwith 92.24 g of dimethyl 1,4-cyclohexyldicarboxylate with 96.91 g ofdiethanolamine, 10.84 g of 30% strength sodium methoxide in methanol,and 52 g of methanol. A homogeneous solution is formed.

The batch is boiled in an oil heating bath under reflux with stirringfor six hours (bath temperature 80° C.). The product begins toprecipitate after about 0.5 hour.

The reaction mixture is left to cool, during which further productcrystallizes out. The precipitated product is subsequently separatedfrom methanol by filtration and then dried. The yield is more than 80%of theory. Table 3a

Obtained accordingly is anN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide according toformula XIIA having two endothermic peaks (1st at about 160° C. and 2ndat about 190° C.) in the DSC as per FIG. 1 and the XRPD spectrum as perFIG. 5 and table 5. This product thus produced produces far-reachingmatting in powder coatings, with a gloss of less than 50 scale divisionsat a 60° angle, table 3a.

Example 3b

The product produced in 3a is dissolved in boiling water, then slowlycooled again and, after crystallization has taken place, briefly washedwith methanol. Table 3a This product exhibits the two endothermic peaks,see FIG. 2, with matting effect present in the resultant powdercoatings, of 29 scale divisions at the 60 degree angle, table 3a.

TABLE 3A End products from batch preparation examples 3a-3b and theircharacterization by GC analysis¹⁾ Example 3a 3b Starting material — 3aPreparation Batch preparation as Boil 3a in deionized water described inexample cool slowly 3a crystallize wash with methanol dry under vacuum¹⁾DEA % by mass 1.22 <0.1¹⁾trans-N,N,N′,N′-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % by mass89.34 91.81 diamide¹⁾cis-N,N,N′,N′-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % by mass 0.740.00 diamide Σ N,N,N′,N′-Tetrakis(2-hydroxyethyl)cyclohexyl-1,4- % bymass 90.08 91.81 diamide Ratio of ¹⁾trans-N,N,N′,N′-tetrakis(2- mol %99.2 1000 hydroxyethyl)cyclohexyl-1,4-diamide to¹⁾cis-N,N,N′,N′-tetrakis(2- mol % 0.8 0.0hydroxyethyl)cyclohexyl-1,4-diamide OH number mg KOH/g 629 — Base number— 22 — DSC: 1^(st) endo. peak - Δ H ° C. - J/g 159-54 164-63  DSC:2^(nd) endo. peak - Δ H ° C. - J/g 186-89 203-124 ¹⁾Analytical values byGC GC after silylation with Silyl 991 (BSTFA-TMCS 99: 1) from Machereyand Nagel order No. 701.490.150. Silylation: 1 ml Silyl 991, 1 mlpyridine, 35 mg reaction product, 35 mg C-18 hydrocarbon as internalstandard, heat for 30 minutes at 80° C. in a closed ampoule. Powdercoating data PC experiment number 3a 3b HAA crosslinker % by mass 3.003.00 CRYLCOAT ® 2617-3 % by mass 60.70 60.70 KRONOS ® 2160 % by mass35.00 35.00 RESIFLOW ® PV 88 % by mass 1.00 1.00 Benzoin % by mass 0.300.30 Total % by mass 100.00 100.00 Curing min @° C. 30 @ 200 30 @ 200Film thickness μm 64-70 70-73 Gloss at 60° 

Sc. div. 30 29 OH number: DIN 53240 Base number: DIN 53176

Preparation Example A Preparation of a β-hydroxyalkylamide of theformula XIIA from dimethyl-1,4-cyclohexyldicarboxylate anddiethanolamine in an extruder

Product description, Substances used manufacturer Diethanolamine (DEA)Dow Chemical Dimethyl 1,4-cyclohexyldicarboxylate Dimethylester of 1,4-(DMCD) trans content 15-35 mol % cyclohexanedicarboxylic acid, EASTMANSodium methoxide 30% strength in methanolOperation Took Place with Three Streams:Stream 1 consisted of DMCDStream 2 consisted of DEAStream 3 consisted of the catalyst, the methanolic sodium methoxidesolution.

The streams were metered so that the molar ratio between dimethyl1,4-cyclohexyldicarboxylate and diethanolamine was 1:1.95.

The total amount of catalyst (only sodium methoxide, calculated onsolvent-free basis), based on the total formula, was 0.50% to 3.0%.

Stream 1 was fed at a rate of 10.0 kg/h into the first barrel of atwin-extruder (ZSK 30, 32 d) (stream temperature 80 to 130° C.).

Stream 2 was fed in at a rate of 9.9 kg/h (stream temperature 65 to 145°C.).

Stream 3 was introduced through a nozzle from entry into the extruderinto stream 2 (0.5 to 2.0 kg/h).

The extruder used consisted of 8 barrels, which were separately heatableand coolable. Barrels 1-5: 160° C., barrels 6-8: 120-160° C.

Barrels 3, 5, and 8 were provided with a vacuum dome (100 to 600 mbar).

The extruder screws were fitted with conveying elements. Ahead of thevacuum domes, kneading blocks were installed.

All of the temperatures represented setpoint temperatures. Regulationtook place via electrical heating or water cooling. The extruder headwas likewise heated electrically (100-160° C.).

The screw speed was 300 rpm. The reaction product was conveyed out ofthe extruder using a gear pump. The total throughput was 20 kg/h.

The end product was cooled via a pipe section or via an extruder and wasguided onto a cooling belt, and cooled further.

Example 4a and 4b

4a

An N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide with theproduct data 4a is prepared in the same way as described in example A inan extruder (Werner and Pfleiderer ZSK 30, 32 d). Table 4

4b

This product, described and produced as in example 4a, isrecrystallized. For this purpose, the product from example 4a isdissolved in deionized water at boiling and then slowly cooled andcrystallized, to convert it back into the solid form. It is subsequentlywashed with methanol and dried in a vacuum drying oven at 50° C. andabout 20 mbar. Table 4

Obtained accordingly is anN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide having twoendothermic peaks (1^(st) at about 160° C. and 2^(nd) at about 190° C.)in the DSC. This product with the two peaks in the DSC as per FIG. 3 andthe XRPD spectrum as per FIG. 7 produces far-reaching matting in powdercoatings, with a gloss of 30 scale divisions at a 60° angle. Table 4.

Comparative Example 4c

A noninventive N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamidewith the DSC as per FIG. 4 was prepared.

This product shows only one endothermic peak in the DSC, at about 190°C., as per FIG. 4, and an XRPD spectrum as per FIG. 6 and table 6. Thepowder coating material produced from it does not exhibit far-reachingmatting, but instead has a gloss of 95 scale divisions at the 60 degreeangle. Table 4

Example 4d

An N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide of theformula XIIA with the product data 4d is prepared in the same way asdescribed in example 1 in an extruder (Werner and Pfleiderer ZSK 30, 32d). Table 4

This product thus produced is run onto a cooling belt and collected.This material is then conditioned thermally under reduced pressure in adrying cabinet at 80° C. for 24 hours, and the resulting product issubsequently comminuted.

This product produces far-reaching matting in powder coating materials,with a gloss of 40 scale divisions at the 60° angle. Table 4

TABLE 4 End products from continuous preparation, examples 4a-4b, andtheir characterization by GC analysis¹⁾ Product examples 4a 4b 4dStarting material — SK 988 Preparation Extruder setting as Dissolve 4ain deionized Extruder setting as described in water described in example1 example 1 cool slowly thermal conditioning crystallize 24 h 80° C.vacuum wash with methanol dry under vacuum ¹⁾DEA fraction % by mass 2.170.11 1.2 ¹⁾trans-N,N,N′,N′-Tetrakis(2- % by mass 84.25 93.72 91.3hydroxyethyl)cyclohexyl-1,4-diamide ¹⁾cis-N,N,N′,N′-Tetrakis(2- % bymass 1.60 0.11 0.66 hydroxyethyl)cyclohexyl-1,4-diamide ΣN,N,N′,N′-Tetrakis(2- % by mass 85.85 93.83 91.96hydroxyethyl)cyclohexyl-1,4-diamide Ratio of¹⁾trans-N,N,N′,N′-tetrakis(2- mol % 98.1 99.9 99.3hydroxyethyl)cyclohexyl-1,4-diamide to ¹⁾cis-N,N,N′,N′-tetrakis(2- mol %1.9 0.1 0.7 hydroxyethyl)cyclohexyl-1,4-diamide OH number mg KOH/g 641625 Base number — 24 1.1 DSC: 1^(st) endo. peak - Δ H ° C. - J/g 162-61 158-50  DSC: 2^(nd) endo. peak - Δ H ° C. - J/g 200-128 188-115¹Analytical values by GC. GC after silylation with Silyl 991 (BSTFA-TMCS99: 1) from Macherey and Nagel order No. 701.490.150. Silylation: 1 mlSilyl 991, 1 ml pyridine, 35 mg reaction product, 35 mg C-18 hydrocarbonas internal standard, heat for 30 minutes at 80° C. in a closed ampoule.Powder coating data PC experiment number 4b 4d HAA crosslinker % by mass3.00 3.00 CRYLCOAT ® 2617-3 % by mass 60.70 60.70 KRONOS ® 2160 % bymass 35.00 35.00 RESIFLOW ® PV 88 % by mass 1.00 1.00 Benzoin % by mass0.30 0.30 Total % by mass 100.00 100.00 Curing Min @° C. 30 @ 200 30 @200 Film thickness μm 52-55 58-68 Gloss at 60° 

Sc. div. 29-30 40 OH number: DIN 53240 Base number: DIN 53176 Endproducts from preparation of comparative examples 4c andcharacterization by GC analysis¹⁾ and powder coating materialComparative example 4c Starting material Preparation - allow to cool atRT ¹⁾DEA % by mass 2.87 ¹⁾trans-N,N,N′,N′-tetrakis(2- % by mass 64.11hydroxyethyl)cyclohexyl-1,4- diamide ¹⁾cis-N,N,N′,N′-tetrakis(2- % bymass 15.84 hydroxyethyl)cyclohexyl-1,4- diamide Σ N,N,N′,N′-tetrakis(2-% by mass 79.95 hydroxyethyl)cyclohexyl-1,4- diamide Ratio of¹⁾trans-N,N,N′,N′- mol % 80.19 tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide to ¹⁾cis-N,N,N′,N′-tetrakis(2- mol % 19.81hydroxyethyl)cyclohexyl-1,4- diamide OH number mg KOH/g sample — Basenumber — — DSC: 1^(st) endo. peak - ΔH ° C. - J/g DSC: 2^(nd) endo.peak - ΔH ° C. - J/g 171-87 Powder coating data PC experiment number 4cHAA crosslinker % by mass 3.00 CRYLCOAT ® 2617-3 % by mass 60.70KRONOS ® 2160 % by mass 35.00 RESIFLOW ® PV 88 % by mass 1.00 Benzoin %by mass 0.30 Total % by mass 100.00 Curing min @° C. 30 @ 200 Filmthickness μm 65-78 Gloss at 60° 

Sc. div. 95

Example 5

A β-hydroxyalkylamide of the formula XIIA was prepared as in example 3a.From it a single crystal was grown. The inventive of the formula XIIAwas investigated by x-ray structural analysis of a single crystal.Comprehensive details relating to the measurement are compiled in annex1.

Annex 1 Single-Crystal X-Ray Structural Analysis

Analytical method: Single Crystal X-ray Structure Analysis“2012-0573602-06D”

Report: WHC 11/11 EKS

Receipt of sample: 2011-02-22Report date: 2011-02-25Objective: Determination of single crystal structure.Compound: N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide,formula XIIA

Crystallization: by the chemist.Crystal dimensions: colorless block, 0.50×0.40×0.40 mm³Code: vestaComments: The asymmetric unit comprises half a molecule.

Experimental Details

The single crystal structure was determined using an instrument fromOxfor Diffraction which was equipped with a CCD detector (Ruby model), aconventional x-ray tube with Cu_(Kα) radiation, Osmic mirror asmonochromator, and a low-temperature unit of the Cryojet type (T=100 K).Data collection was carried out in phi and omega scans. Data collectionand reduction took place using Crysalis (Oxford Diffraction 2007).

Structural resolution and refinement took place using SHELXTL (V. 6.10,Sheldrick, University of Göttingen, 2000). All non-hydrogen atoms wererefined anisotropically. The hydrogen atoms were refined as ridinggroups.

Tables

TABLE A Crystal data and data relating to structural refinement forvesta. Identification code vesta Empirical formula C16H30N2O6 Formulaweight 346.42 Temperature 100 K Wavelength 1.54178 Å Crystal systemOrthorhombic Space group Pbca Unit cell a = 10.06350(10) Å = 90°. b =11.85290(10) Å = 90°. c = 14.6275(2) Å = 90°. Volume 1744.79(3) Å³ Z 4Density (calculated) 1.319 Mg/m³ Absorption coefficient 0.832 mm⁻¹F(000) 752 Crystal dimensions 0.50 × 0.40 × 0.40 mm³ Theta range fordata collection 6.05 to 65.68°. Index range −11 ≦ h ≦ 10, −12 ≦ k ≦ 14,−14 ≦ l ≦ 17 Number of reflections collected 9191 Symmetry-independentreflections 1482 [R(int) = 0.0345] Completeness to theta = 65.68° 98.5%Correction for absorption Crysalis Refinement Full-matrix least-squareson F² Data/restraints/parameters 1482/0/111 Goodness-of-fit on F² 1.065Final R values [I > 2sigma(I)] R1 = 0.0316, wR2 = 0.0792 R values (alldata) R1 = 0.0358, wR2 = 0.0817 Largest difference peaks 0.199 and−0.189 e · Å⁻³

TABLE B Bond lengths [Å] and angles [°] for vesta. O(1)—C(4) 1.2478(15)O(2)—C(6) 1.4221(15) O(3)—C(8) 1.4205(16) N(1)—C(4) 1.3479(16) N(1)—C(5)1.4741(15) N(1)—C(7) 1.4727(15) C(1)—C(3)#1 1.5291(17) C(1)—C(2)1.5398(16) C(2)—C(4) 1.5189(17) C(2)—C(3) 1.5405(16) C(3)—C(1)#11.5291(17) C(5)—C(6) 1.5182(16) C(7)—C(8) 1.5159(17) C(4)—N(1)—C(5)124.59(10) C(4)—N(1)—C(7) 117.87(10) C(5)—N(1)—C(7) 117.54(9)C(3)#1—C(1)—C(2) 110.62(10) C(4)—C(2)—C(1) 111.04(10) C(4)—C(2)—C(3)108.67(10) C(1)—C(2)—C(3) 110.09(10) C(1)#1—C(3)—C(2) 111.18(10)O(1)—C(4)—N(1) 119.97(11) O(1)—C(4)—C(2) 120.15(10) N(1)—C(4)—C(2)119.84(10) N(1)—C(5)—C(6) 113.66(9) O(2)—C(6)—C(5) 110.97(10)N(1)—C(7)—C(8) 113.52(10) O(3)—C(8)—C(7) 113.31(10) Symmetry operationsfor generating equivalent atoms: #1 −x + 1, −y + 1, −z

TABLE C Torsional angles [°] for vesta. C(3)#1—C(1)—C(2)—C(4) 177.11(9)C(3)#1—C(1)—C(2)—C(3) 56.72(14) C(4)—C(2)—C(3)—C(1)#1 −178.85(9)C(1)—C(2)—C(3)—C(1)#1 −57.04(14) C(5)—N(1)—C(4)—O(1) 176.19(10)C(7)—N(1)—C(4)—O(1) −3.65(16) C(5)—N(1)—C(4)—C(2) −6.21(16)C(7)—N(1)—C(4)—C(2) 173.95(10) C(1)—C(2)—C(4)—O(1) −54.62(14)C(3)—C(2)—C(4)—O(1) 66.61(14) C(1)—C(2)—C(4)—N(1) 127.78(11)C(3)—C(2)—C(4)—N(1) −110.98(12) C(4)—N(1)—C(5)—C(6) 80.57(13)C(7)—N(1)—C(5)—C(6) −99.58(12) N(1)—C(5)—C(6)—O(2) 61.92(13)C(4)—N(1)—C(7)—C(8) 86.25(13) C(5)—N(1)—C(7)—C(8) −93.60(12)N(1)—C(7)—C(8)—O(3) 73.97(13) Symmetry operations for generatingequivalent atoms: #1 −x + 1, −y + 1, −z

FIG. 11:

Calculated powder diffractogram based on the single crystal structuraldetermination ofN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide (vesta sample)

1. A powder coating composition, comprising: A) a polymer comprising acarboxylate group and having an acid number of 5 to 250 mg KOH/g and aglass transition temperature T_(g) of greater than 40° C.; and B) aβ-hydroxyalkylamide having two or three or four β-hydroxyalkylamidegroups per molecule of the formula I

wherein: R¹ and R² are, independently of one another, identical ordifferent radicals selected from the group consisting of an alkylradical, a cycloalkyl radical, an aryl radical, an aralkyl radical andan alkenyl radical having 1-24 carbon atoms, said radicals optionallycomprising a heteroatom, a functional group, or both, and where R¹ mayalso be hydrogen, such that R² is optionally:

A is A¹, A² or A³:

 such that radicals R³ are, independently of one another, identical ordifferent radicals selected from the group consisting of hydrogen, analkyl radical, a cycloalkyl radical, an aryl radical, an aralkyl radicaland an alkenyl radical having 1-24 carbon atoms, said radicalsoptionally comprising a heteroatom, a functional group, or both, suchthat two or more substituents R³ are optionally linked with one anotherto form rings; and the β-hydroxyalkylamide is present in solid formbelow 150° C.; C) optionally auxiliaries additives, or both; wherein aratio of the β-hydroxyalkylamide groups to the carboxylate groups isbetween 0.5:1 to 1.5:1.
 2. The powder coating composition of claim 1,wherein the β-hydroxyalkylamide derives from β-hydroxyalkylaminescomprising alkyl groups having at least 2 to 10 carbon atoms in thehydrocarbon framework as starting materials, said alkyl groups beinglinear, branched or cyclic and optionally substituted by at least oneheteroatom, and optionally comprising at least one functional group suchthat the β-hydroxyalkylamines optionally comprise an additional alkylradical on the nitrogen.
 3. The powder coating composition of claim 1,comprising β-hydroxyalkylamides of N-alkyl-1,2-alkanolamines and/or ofN,N-bis-2-hydroxyalkylamines and esters of cyclohexanedicarboxylicacids.
 4. The powder coating composition of claim 1, wherein theβ-hydroxyalkylamines are hydroxylamines of the formulae II and/or III:

wherein R¹ is hydrogen, methyl, ethyl, or propyl, R² is methyl;

wherein radicals R¹ simultaneously or independently of one another arehydrogen, methyl, ethyl, or propyl.
 5. The powder coating composition ofclaim 1, wherein the following compounds are starting materials forpreparing the β-hydroxyalkylamide: diethanolamine (DEA),di-isopropropanolamine (DIPA), di-sec-butanolamine,N-methylethanolamine, N-methylisopropanolamine.
 6. The powder coatingcomposition of claim 1, wherein the substituent A derives from1,2-substituted, 1,3-substituted, and 1-4-substitutedcyclohexanedicarboxylic acid derivatives.
 7. The powder coatingcomposition of claim 1, wherein the β-hydroxyalkylamide is prepared fromcompounds of the formula IV:

wherein radicals R⁴ simultaneously or independently of one another aremethyl, ethyl, propyl, or butyl.
 8. The powder coating composition ofclaim 1, wherein at least one 1,4-substituted cyclohexanedicarboxylicester is a starting compound.
 9. The powder coating composition of claim1, wherein the β-hydroxyalkylamide B) has at least one of the followingformulae:

wherein: R² is methyl, or

where R^(1A) is hydrogen and R^(1B) is methyl, ethyl, or propyl, orR^(1A) is methyl, ethyl, or propyl and R^(1B) is hydrogen; A is a1,4-disubstituted cyclohexane ring of the formula:

a trans content of A is ≧70 mol %; and at least one β-hydroxyalkylamideB) is present in solid form below 150° C.
 10. The powder coatingcomposition of claim 1, comprising β-hydroxyalkylamides of dialkyl1,4-cyclohexyldicarboxylates, with a trans content, based on theposition of the carboxyl groups on the cyclohexyl ring, of greater thanor equal to 70 mol %.
 11. The powder coating composition of claim 1,wherein: the β-hydroxyalkylamide consists of dimethyl1,4-cyclohexyldicarboxylate and diethanolamine having fourβ-hydroxyalkylamide groups per molecule of the formula XII:

 having a trans content on the cyclohexyl ring of greater than or equalto 70 mol.
 12. The powder coating composition of claim 1, wherein theβ-hydroxyalkylamide is present in solid form below 150° C.
 13. Thepowder coating composition of claim 1, comprising a polyester A)comprising at least one carboxylate group and having: a glass transitiontemperature T_(g) in a range from 40 to 80° C. an acid number variedfrom 5-250 mg KOH/g; an OH number of less than 15 mg KOH/g; and anaverage molecular weight M_(w) of 1000 to 10 000 g/mol.
 14. The powdercoating composition of claim 1, comprising an acrylate polymer A)comprising at least one carboxylate group and having: an OH number ofless than 10 mg KOH/g; an acid number of 10 to 350 mg KOH/g; a Tg of 40to 110° C.; and an M_(W) of 500 to 50 000 g/mol.
 15. The powder coatingcomposition of claim 1, comprising at least one co-crosslinker based onepoxy resins and/or β-hydroxyalkylamides different from theβ-hydroxyalkylamide B).
 16. A method for producing the powder coatingcomposition of claim 1, the method comprising conducting joint extrusionof all the components in a melt at temperatures between 80 to 150° C.17. A process for producing a coating for a matt surface, the processcomprising applying the powder coating composition of claim 1 to asurface, wherein the coating has a gloss to DIN 67530/ISO 2813 of <50 atan incident angle of
 60. 18. The powder coating composition of claim 1,comprising a N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamideaccording to the formula XIIA as component B),

having the following parameters: a trans content on the cyclohexyl ringof the N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide ofgreater than or equal to 70 mol %, based on the total amount of all ofthe isomers of N,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamidethat are present; two endothermic peaks according to DSC analysis(differential scanning calorimetry), where peak 1 is situated in theregion of 140-170° C. with a maximum of 155-165° C., and peak 2 issituated in the region of 170-210° C. with a maximum of 175-207° C.; aratio of the enthalpies of the peak 1 to the peak 2 is 1:1 to 1:5; andthe following peaks in the XRPD spectrum of the powder sample in thex-ray diffractometer, measured with Cu Kα radiation (1.541 Å): Degrees2theta ± Peak #. 0.2 degree 2theta d (Å) 1 14.90 5.94 2 16.70 5.31 317.40 5.09 4 21.20 4.19 5 21.60 4.11 6 26.00  3.43.


19. The powder coating composition of claim 18, having a trans contenton the cyclohexyl ring of greater than or equal to 92 mol %, based onthe total amount of all of the isomers ofN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide that arepresent.
 20. The powder coating composition of claim 18, wherein theβ-hydroxyalkylamide of the formula XIIA is present in solid form below175° C.
 21. The powder coating composition of claim 18, wherein aconcentration of all of the isomers ofN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide in the endproduct after its production is 75% by mass.
 22. The powder coatingcomposition of claim 18, wherein a ratio of the enthalpies of the peak 1to the peak 2 is 1:1 to 1:3.
 23. The powder coating composition of claim18, wherein theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide, according tox-ray structural analysis of a single crystal, has the followingparameters: Crystal system: Orthorhombic Space group: Pbca Unit celldimensions: a = 10.06350(10) Å α = 90°[[.]] b = 11.85290(10) Å β =90°[[.]] c = 14.6275(2) Å γ = 90°[[.]] Volume: 1744.79(3) Å³.


24. A process for producing a coating for a matt surface, the processcomprising applying the powder coating composition of claim 18 to asurface, wherein the coating has matt surfaces with <50 gloss units,measured as reflectometer values to DIN 67530/ISO 2813 with an incidentangle of 60°.
 25. The process of claim 24, wherein theN,N,N′,N′-tetrakis(2-hydroxyethyl)cyclohexyl-1,4-diamide, according tox-ray structural analysis of a single crystal, has the followingparameters: Crystal system: Orthorhombic Space group: Pbca Unit celldimensions: a = 10.06350(10) Å α = 90°. b = 11.85290(10) Å β = 90°. c =14.6275(2) Å γ = 90°. Volume: 1744.79(3) Å³.

26-27. (canceled)